public inbox for netdev@vger.kernel.org
 help / color / mirror / Atom feed
From: Kyle Zeng <zengyhkyle@gmail.com>
To: davem@davemloft.net
Cc: yoshfuji@linux-ipv6.org, dsahern@kernel.org, edumazet@google.com,
	kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org
Subject: net: ipv6: raw: fixes null pointer deference in rawv6_push_pending_frames
Date: Fri, 6 Jan 2023 14:19:52 -0700	[thread overview]
Message-ID: <Y7iQeGb2xzkf0iR7@westworld> (raw)

The local variable csum_skb is initialized to NULL. It is posible that the skb_queue_walkloop
does not assign csum_skb to a real skb. After the loop, skb will be set to csum_skb, which
means skb is set to NULL. Then when the skb is used later, null pointer deference bug happens.
This patch catches the case and avoids the oops.

Signed-off-by: Kyle Zeng <zengyhkyle@gmail.com>
---
 net/ipv6/raw.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index a06a9f847..982a8b77a 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -556,6 +556,9 @@ static int rawv6_push_pending_frames(struct sock *sk, struct flowi6 *fl6,
 		skb = csum_skb;
 	}
 
+	if (skb == NULL)
+		goto out;
+
 	offset += skb_transport_offset(skb);
 	err = skb_copy_bits(skb, offset, &csum, 2);
 	if (err < 0) {
-- 
2.34.1


             reply	other threads:[~2023-01-06 21:21 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-06 21:19 Kyle Zeng [this message]
2023-01-06 22:55 ` net: ipv6: raw: fixes null pointer deference in rawv6_push_pending_frames Jakub Kicinski
2023-01-06 23:12   ` Kyle Zeng
2023-01-06 23:57     ` Jakub Kicinski
2023-01-08 22:09       ` Kyle Zeng
2023-01-09  8:45     ` Eric Dumazet
2023-01-09 10:05       ` Herbert Xu
2023-01-09 10:08         ` Eric Dumazet
2023-01-10  0:59           ` [PATCH] ipv6: raw: Deduct extension header length " Herbert Xu
2023-01-11 12:50             ` patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Y7iQeGb2xzkf0iR7@westworld \
    --to=zengyhkyle@gmail.com \
    --cc=davem@davemloft.net \
    --cc=dsahern@kernel.org \
    --cc=edumazet@google.com \
    --cc=kuba@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=yoshfuji@linux-ipv6.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox